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Gridview dataBound add hyperlink to column data from code behind

Using grid view binding it from code behind:
I want to bind a particular column data into a hyper link so when it clicked it should do a download.
How to do that ?
Below is my code :
for (int i = 0; i <= tbl.Columns.Count - 1; i++)
{
Telerik.Web.UI.GridBoundColumn boundfield = new Telerik.Web.UI.GridBoundColumn();
if (tbl.Columns[i].ColumnName.ToString() == "Row")
{
LinkButton lkbtn = new LinkButton();
lkbtn.CommandName = i;
lkbtn.CommandArgument = "dwnld";
lkbtn.Font.Underline = true;
lkbtn.Text = tbl.Columns(i).ColumnName.ToString();
boundfield.DataField = tbl.Columns(i).ColumnName.ToString()
boundfield.HeaderText = tbl.Columns(i).ColumnName.ToString();
GridView2.MasterTableView.Columns.Add(boundfield);
}
}

Why not use grid template column with link button.
<telerik:GridTemplateColumn>
<ItemTemplate>
<asp:LinkButton ID="btnDownload" OnClick="btnDownload_Click" runat="server">Download Something</asp:LinkButton>
</ItemTemplate>
</telerik:GridTemplateColumn>
protected void btnDownload_Click(object sender, EventArgs e)
{
LinkButton lbBtn = sender as LinkButton;
GridDataItem item = (GridDataItem)(sender as LinkButton).NamingContainer;
// Use item to get other details
...
...
}

How to save changes from DropDownList to sql database?

I edited a DataGrid column so the location is now a DropDownList, which works fine. It populates the DropDownList from the database.
<asp:TemplateColumn HeaderText="Trailer Location">
<itemtemplate>
<asp:DropDownList ID="ddlTrailerLoc" runat="server" OnSelectedIndexChanged="ddlTrailerLoc_SelectedIndexChanged">
</asp:DropDownList>
<asp:HiddenField ID="hdlTrailerLoc" runat="server" Value='<%#Eval("TrailerLocation")%>' />
</itemtemplate>
</asp:TemplateColumn>
But when I change the value in the DropDownList I don't know how to save the changes made to the database.
protected void PopulateDDLs(DropDownList ddlTrailerLoc)
{
DataSet dsTrailerLocation = DataUtils.GetAllGenSmall(Company.Current.CompanyID, "Description", "", 1, false, "Description", false, "TrailerLocationNOCODE", 0);
if (dsTrailerLocation.Tables[0].Rows.Count > 0)
{
ddlTrailerLoc.DataSource = dsTrailerLocation;
ddlTrailerLoc.DataValueField = "Description";
ddlTrailerLoc.DataTextField = "Description";
ddlTrailerLoc.DataBind();
}
else
{
ddlTrailerLoc.Items.Insert(0, new ListItem("No Locations Entered", "0"));
}
}
protected void dgList_ItemCreated(object sender, DataGridItemEventArgs e)
{
if (e.Item.ItemType != ListItemType.Header && e.Item.ItemType != ListItemType.Pager && e.Item.ItemType != ListItemType.Footer)
{
DropDownList ddlTrailerLocation = e.Item.FindControl("ddlTrailerLoc") as DropDownList;
if (ddlTrailerLocation != null)
{
PopulateDDLs(ddlTrailerLocation);
//set the value in dropdown
HiddenField hdlTrailerLoc = e.Item.FindControl("hdlTrailerLoc") as HiddenField;
if (hdlTrailerLoc != null)
{
ddlTrailerLocation.SelectedValue = hdlTrailerLoc.Value;
}
}
}
}
I tried creating this ddlTrailerLoc_SelectedIndexChanged method but the event doesn't run.
protected void ddlTrailerLoc_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList list = (DropDownList)sender;
TableCell cell = list.Parent as TableCell;
DataGridItem item = cell.Parent as DataGridItem;
int selectedIndex = item.ItemIndex;
string selectedItem = item.Cells[0].Text;
// now save your work here and rebind the grid.
Trailer.UpdateTrailer(int.Parse(TrailerID), Company.Current.CompanyID,
txtTrailerReg.Text,
ddlTrailerLocation.Text);
ddlTrailerLocation.DataValueField = "Description";
ddlTrailerLocation.DataTextField = "Description";
ddlTrailerLocation.DataBind();
}

Please add AutoPostBack="True" in dropdown. It will work
<asp:DropDownList ID="ddlTrailerLoc" runat="server" OnSelectedIndexChanged="ddlTrailerLoc_SelectedIndexChanged" AutoPostBack="True"></asp:DropDownList>
Please write code as below
protected void ddlTrailerLoc_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList ddlTrailerLoc=sender as DropDownList;
if(ddlTrailerLoc!=null)
{
int trailerId=int.Parse(ddlTrailerLoc.SelectedValue.ToString());
//Save selected value in Database
// now save your work here and rebind the grid.
Trailer.UpdateTrailer(trailerId, Company.Current.CompanyID,
txtTrailerReg.Text,
ddlTrailerLoc.Text);
ddlTrailerLocation.DataValueField = "Description";
ddlTrailerLocation.DataTextField = "Description";
ddlTrailerLocation.DataBind();
}
}

How to fire click event of the LinkButton in gridview and Show PopUp window in asp.net

I have tried to build one gridview with dynamic columns based the data source using the template fields in asp.net through code behind.
For that, to implement we have developed one class DynamicTemplate which implements the ITemplate interface. In that template fields i have inserted the LinkButton in each cell and when i click that cell link button i need to show the one Popup with selected cell value.
For Detailed Sample Please download from this link
For that I have created one Default.asxp page and wrote the following.
public partial class Default : System.Web.UI.Page
{
DataTable dt;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
GenateGridView();
}
private void GenateGridView()
{
TemplateField tempField;
DynamicTemplate dynTempItem;
LinkButton lnkButton;
Label label;
GridView gvDynamicArticle = new GridView();
gvDynamicArticle.Width = Unit.Pixel(500);
gvDynamicArticle.BorderWidth = Unit.Pixel(0);
gvDynamicArticle.Caption = "<div>Default Grid</div>";
gvDynamicArticle.AutoGenerateColumns = false;
DataTable data = getBindingData();
for (int i = 0; i < data.Columns.Count; i++)
{
tempField = new TemplateField();
dynTempItem = new DynamicTemplate(ListItemType.AlternatingItem);
lnkButton = new LinkButton();
lnkButton.ID = string.Format("lnkButton{0}", i);
lnkButton.Visible = true;
string ColumnValue = data.Columns[i].ColumnName;
tempField.HeaderText = ColumnValue;
if (ColumnValue == "EmpName")
{
label = new Label();
label.ID = string.Format("Label{0}", i);
dynTempItem.AddControl(label, "Text", ColumnValue);
label.Width = 100;
}
else
{
dynTempItem.AddControl(lnkButton, "Text", ColumnValue);
lnkButton.Click += lnkButton_Click;
}
tempField.ItemTemplate = dynTempItem;
gvDynamicArticle.Columns.Add(tempField);
//////grdUserPivotDateTwo.Columns.Add(tempField);
}
gvDynamicArticle.DataSource = data;
gvDynamicArticle.DataBind();
divContainer.Controls.Add(gvDynamicArticle);
}
void lnkButton_Click(object sender, EventArgs e)
{
// showing cell values in popUp here..
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('cell clicked')");
}
private DataTable getBindingData()
{
dt = new DataTable();
dt.Columns.Add(new DataColumn("EmpName"));
dt.Columns.Add(new DataColumn("Monday"));
dt.Columns.Add(new DataColumn("TuesDay"));
dt.Columns.Add(new DataColumn("WednesDay"));
dt.Columns.Add(new DataColumn("ThursDay"));
dt.Rows.Add("EmpOne", "p", "p", "p", "a");
dt.Rows.Add("EmpTwo", "p", "a", "p", "p");
dt.Rows.Add("EmpThree", "p", "p", "p", "a");
dt.Rows.Add("EmpFour", "p", "a", "p", "p");
dt.Rows.Add("EmpFive", "p", "p", "p", "a");
dt.Rows.Add("EmpSix", "a", "p", "p", "p");
return dt;
}
}
and corresponding DynamicTemplate class is
public class DynamicTemplate : System.Web.UI.ITemplate
{
System.Web.UI.WebControls.ListItemType templateType;
System.Collections.Hashtable htControls = new System.Collections.Hashtable();
System.Collections.Hashtable htBindPropertiesNames = new System.Collections.Hashtable();
System.Collections.Hashtable htBindExpression = new System.Collections.Hashtable();
public DynamicTemplate(System.Web.UI.WebControls.ListItemType type)
{
templateType = type;
}
public void AddControl(WebControl wbControl, String BindPropertyName, String BindExpression)
{
htControls.Add(htControls.Count, wbControl);
htBindPropertiesNames.Add(htBindPropertiesNames.Count, BindPropertyName);
htBindExpression.Add(htBindExpression.Count, BindExpression);
}
public void InstantiateIn(System.Web.UI.Control container)
{
PlaceHolder ph = new PlaceHolder();
for (int i = 0; i < htControls.Count; i++)
{
//clone control
Control cntrl = CloneControl((Control)htControls[i]);
switch (templateType)
{
case ListItemType.Header:
break;
case ListItemType.Item:
ph.Controls.Add(cntrl);
break;
case ListItemType.AlternatingItem:
ph.Controls.Add(cntrl);
ph.DataBinding += new EventHandler(Item_DataBinding);
break;
case ListItemType.Footer:
break;
}
}
ph.DataBinding += new EventHandler(Item_DataBinding);
container.Controls.Add(ph);
}
public void Item_DataBinding(object sender, System.EventArgs e)
{
PlaceHolder ph = (PlaceHolder)sender;
GridViewRow ri = (GridViewRow)ph.NamingContainer;
for (int i = 0; i < htControls.Count; i++)
{
if (htBindPropertiesNames[i].ToString().Length > 0)
{
Control tmpCtrl = (Control)htControls[i];
String item1Value = (String)DataBinder.Eval(ri.DataItem, htBindExpression[i].ToString());
Control ctrl = ph.FindControl(tmpCtrl.ID);
Type t = ctrl.GetType();
System.Reflection.PropertyInfo pi = t.GetProperty(htBindPropertiesNames[i].ToString());
pi.SetValue(ctrl, item1Value.ToString(), null);
}
}
}
private Control CloneControl(System.Web.UI.Control src_ctl)
{
Type t = src_ctl.GetType();
Object obj = Activator.CreateInstance(t);
Control dst_ctl = (Control)obj;
PropertyDescriptorCollection src_pdc = TypeDescriptor.GetProperties(src_ctl);
PropertyDescriptorCollection dst_pdc = TypeDescriptor.GetProperties(dst_ctl);
for (int i = 0; i < src_pdc.Count; i++)
{
if (src_pdc[i].Attributes.Contains(DesignerSerializationVisibilityAttribute.Content))
{
object collection_val = src_pdc[i].GetValue(src_ctl);
if ((collection_val is IList) == true)
{
foreach (object child in (IList)collection_val)
{
Control new_child = CloneControl(child as Control);
object dst_collection_val = dst_pdc[i].GetValue(dst_ctl);
((IList)dst_collection_val).Add(new_child);
}
}
}
else
{
dst_pdc[src_pdc[i].Name].SetValue(dst_ctl, src_pdc[i].GetValue(src_ctl));
}
}
return dst_ctl;
}
}
Here the Data showing in gridview is fine. Here the Issues are when i click on the linkButton the page reloads and no grid is displaying after the postback.
second issue is, for LinkButton the Click Event is not firing.
Please provide me the help full information/Sample to show the modal window when we click on the linkButton of the gridview.

You need to use ajax model popup expender.
Design a panel with your fields and use the model popup expender to display that popup
This link has the sample of it
www.asp.net/ajaxlibrary/ajaxcontroltoolkitsamplesite/modalpopup/modalpopup.aspx
and in your link button click
you have to use show method to open popup

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
GenateGridView();
}
this code is generating a gridview only if it is not a postback, but when you click a linkbutton a postpack occurs and that's the reason why gridview doesnt show again when you click on the linkbutton.
add the following code(additional else part included to your if code) to show gridview when you click lnkButton
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
GenateGridView();
else
{
string ctrlName = Request.Params.Get("__EVENTTARGET").Trim();
if (!String.IsNullOrEmpty(ctrlName))
{
if (ctrlName.StartsWith("lnkButton"))
{
GenateGridView();
}
}
}
}

It will be a good choice to use CommandName property for the linkbutton on the Gridview and give it a specfic name and in the code file and exactly work with it in RowCommand event of your GridView as following in this example :
first here is the .aspx file :
<div>
<asp:GridView ID="GridViewStudents" runat="server" AutoGenerateColumns="False" OnRowCommand="GridViewStudents_RowCommand">
<Columns>
<asp:TemplateField HeaderText="Stud_ID" Visible="False">
<ItemTemplate>
<asp:Label ID="LabelStudID" runat="server" Text='<%# Eval("Stud_ID") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="FKFather_ID" Visible="False">
<ItemTemplate>
<asp:Label ID="LabelFkFatherID" runat="server" Text='<%# Eval("Fk_Father_ID") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Student Name">
<ItemTemplate>
<asp:Label ID="LabelStudName" runat="server" Text='<%# Eval("Stud_Name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Class Name">
<ItemTemplate>
<asp:Label ID="LabelRowlevelName" runat="server" Text='<%# Eval("Stud_Level_Row_Name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Delete">
<ItemTemplate>
<asp:ImageButton ID="ImageButtonDelete" runat="server" CommandArgument='<%# Eval("Stud_ID") %>' CommandName="Remove" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</div>
<div style="direction: ltr">
<asp:Panel ID="Panel1" runat="server" Visible="false">
<asp:Label ID="Labelpopupmessage" runat="server" Text=""></asp:Label>
<br />
<asp:Button ID="Buttonaccept" runat="server" Text="نعم" OnClick="Buttonaccept_Click" />
<asp:Button ID="Buttoncancel" runat="server" Text="لا" OnClick="Buttoncancel_Click" />
</asp:Panel>
<asp:HiddenField ID="HiddenField1" runat="server" />
<asp:ModalPopupExtender runat="server" ID="ModalPopupExtenderStudent" PopupControlID="ButtonSubmit" TargetControlID="HiddenField1" CancelControlID="Buttoncancel">
</asp:ModalPopupExtender>
</div>
and here is the code implementation of my illustration :
protected void GridViewStudents_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Remove")
{
// I stored the ID of the selected Student I want to delete in a viewstate.
ViewState.Add("DeletedStudDetailID",Convert.ToInt32(e.CommandArgument));
ModalpopupExtender.Show();
}
}
// Here in the accept delete button I used that code ..
protected void Buttonaccept_Click(object sender, EventArgs e)
{
try
{
if (ViewState["DeletedStudDetailID"] != null)
{
StudentDetail StudDet = Data.StudentDetails.Single(SD => SD.Fk_Stud_ID == Convert.ToInt32(ViewState["DeletedStudDetailID"]));
Data.StudentDetails.DeleteOnSubmit(StudDet);
Student Stud = Data.Students.Single(S => S.Stud_ID == Convert.ToInt32(ViewState["DeletedStudDetailID"]));
Data.Students.DeleteOnSubmit(Stud);
Data.SubmitChanges();
}
this.ResultMessage = "Delete Done Sucessfully !!";
}
catch
{
this.ErrorMessage = "Delete operation disordered !!";
}
finally
{
ModalPopExtender.Hide();
}
}
I hope it helps in your issue and I wish you a happy day :) !!

First, your GridView will be created when calling GenateGridView method, so you have to call this method everytime you do post back, then your Page_Load should be
protected void Page_Load(object sender, EventArgs e)
{
GenateGridView();
}
Second, I would present you the other way to add LinkButton to GridView dynamically.
I modified your GenateGridView to just add only label into DynamicTemplate, also add this line gvDynamicArticle.RowDataBound += new GridViewRowEventHandler(gvDynamicArticle_RowDataBound); to handle adding LinkButton.
private void GenateGridView()
{
TemplateField tempField;
DynamicTemplate dynTempItem;
Label label;
GridView gvDynamicArticle = new GridView();
gvDynamicArticle.Width = Unit.Pixel(500);
gvDynamicArticle.BorderWidth = Unit.Pixel(0);
gvDynamicArticle.Caption = "<div>Default Grid</div>";
gvDynamicArticle.AutoGenerateColumns = false;
gvDynamicArticle.RowDataBound += new GridViewRowEventHandler(gvDynamicArticle_RowDataBound);
DataTable data = getBindingData();
for (int i = 0; i < data.Columns.Count; i++)
{
tempField = new TemplateField();
dynTempItem = new DynamicTemplate(ListItemType.AlternatingItem);
string ColumnValue = data.Columns[i].ColumnName;
tempField.HeaderText = ColumnValue;
label = new Label();
label.ID = string.Format("Label{0}", i);
dynTempItem.AddControl(label, "Text", ColumnValue);
label.Width = 100;
tempField.ItemTemplate = dynTempItem;
gvDynamicArticle.Columns.Add(tempField);
}
gvDynamicArticle.DataSource = data;
gvDynamicArticle.DataBind();
divContainer.Controls.Add(gvDynamicArticle);
}
I implement like this in RowDataBound event handler of the GridView to add LinkButton and hide the Label which we added it before:
protected void gvDynamicArticle_RowDataBound(object sender, GridViewRowEventArgs e)
{
for (int j = 1; j < e.Row.Cells.Count; j++)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
LinkButton lnkButton = new LinkButton();
lnkButton.ID = string.Format("lnkButton{0}{1}", e.Row.DataItemIndex, j);
lnkButton.Click += new EventHandler(lnkButton_Click);
Label tempLabel = e.Row.FindControl("Label" + j) as Label;
lnkButton.Text = tempLabel.Text;
lnkButton.CommandArgument = tempLabel.Text;
tempLabel.Visible = false;
e.Row.Cells[j].Controls.Add(lnkButton);
}
}
}
You can also set any value to CommandArgument of LinkButton, then you can show it in the alert.
Final, seems you want to show some value in the alert, you may code like this
public void lnkButton_Click(object sender, EventArgs e)
{
// showing cell values in popUp here..
LinkButton lnk = (LinkButton)sender;
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('cell clicked, value " + lnk.CommandArgument + "')", true);
}

how to bind value to hyperlink in gridview in c# code behind

I have a custom grid on which i have binded data in my c# code behind. I have given a hyperlink field to one of my column. If i click the hyperlink value, it should navigate to the details page of that hyperlink value. The code is given below,
protected void grd_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
HyperLink myLink = new HyperLink();
myLink.Text = e.Row.Cells[2].Text;
e.Row.Cells[2].Controls.Add(myLink);
myLink.NavigateUrl = "Estimation.aspx?EstimateID=" + EstimateID + "&VersionNo=" + VersionNo;
}
}
If i click the link, the page is getting navigated, but i am not getting the details which are already pre-loaded in that page. Please give me suggestions on how to incorporate this.
Thanks

You can use this to redirect, read this
<asp:HyperLink ID="HyperLink1"
runat="server"
NavigateUrl="Default2.aspx">
HyperLink
</asp:HyperLink>
to add attribute with link just add
HyperLink1.Attributes.Add ("");

You need to do a small change in the RowDataBound event
myLink.Attributes.Add("href"," your url");

You need to fetch the values for EstimateID and VersionNo from the grid row data. Take a look at the documentation for GridViewRowEventArgs and you'll see there's a .Row property.
So your code needs to be something like:
myLink.NavigateUrl = "Estimation.aspx?EstimateID=" + e.Row.Cells[4].Text + "&VersionNo=" + e.Row.Cells[5].Text;
Or, maybe you need to get to the data item associated with the grid row, in which case take a look at e.Row.DataItem, the GridViewRow.DataItem property. This DataItem will need to be cast to the type of data you've bound to the grid in order to fetch the data from it, which might be something like:
((MyCustomDataRow)e.Row.DataItem).EstimateID

Try below solution :
Page-1 that is your list page :
ASPX code :
<asp:GridView ID="GridView1" runat="server"
onrowdatabound="GridView1_RowDataBound">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:HyperLink ID="HyperLink1" runat="server">HyperLink</asp:HyperLink>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
Code Behind :
protected void Page_Load(object sender, EventArgs e)
{
List<Data> lstData = new List<Data>();
for (int index = 0; index < 10; index++)
{
Data objData = new Data();
objData.EstimateID = index;
objData.VersionNo = "VersionNo" + index;
lstData.Add(objData);
}
GridView1.DataSource = lstData;
GridView1.DataBind();
}
public class Data
{
public int EstimateID { get; set; }
public string VersionNo { get; set; }
}
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
HyperLink HyperLink1 = e.Row.FindControl("HyperLink1") as HyperLink;
HyperLink1.NavigateUrl = "Details.aspx?EstimateID=" + e.Row.Cells[1].Text + "&VersionNo=" + e.Row.Cells[2].Text;
}
}
Page-2 that is your details page :
Code behind :
protected void Page_Load(object sender, EventArgs e)
{
Response.Write(Request.QueryString["EstimateID"].ToString());
Response.Write(Request.QueryString["VersionNo"].ToString());
}

find control inside datalist on page load

I want to find an item in the datalist on page load method this is my code
protected void Page_Load(object sender, EventArgs e)
{
//some code here
for (int i = 0; i < count ; i++)
{
LinkButton LinkButton6 = (LinkButton)sender;
DataListItem item = (DataListItem)LinkButton6.NamingContainer;
LinkButton lnkbtn6 = (LinkButton)DataList1.Items[item.ItemIndex].FindControl("LinkButton6");
}
}
but this error appears to me :Unable to cast object of type 'ASP.default2_aspx' to type 'System.Web.UI.WebControls.LinkButton'.

Page_Load is not an event triggered by LinkButton so sender cannot be a LinkButton. It is a Page event. Use OnItemDataBound instead
Markup
<asp:DataList OnItemDataBound="DataList1_OnItemDataBound" runat="server" ID="MdataList">
<ItemTemplate>
<asp:LinkButton runat="server" ID="LinkButton6" Text="Text"></asp:LinkButton>
</ItemTemplate>
</asp:DataList>
Codebehind
protected void Page_Load(object sender, EventArgs e)
{
}
protected void DataList1_OnItemDataBound(object sender, DataListItemEventArgs e)
{
LinkButton lnkBtn6 = (LinkButton)e.Item.FindControl("LinkButton6");
lnkBtn6.Text = "Some Text Here";
}

On this line:
LinkButton LinkButton6 = (LinkButton)sender;
the sender object is the Page, not LinkButton, isn't it?